snap oversteer..how to fight it

[TAK82]

I've seen and heard how many FWD owner's lost their car's due to snap oversteer..

it's mostly the cause of the rear end suspension being to stiff..

drift car's use stiff suspension's and thicke roll bars to induce the rear tail to break loose to initiate drifitng..

i see alot of civic owner's put coilovers and thicker sway bar's on their honda civc..

this may seem's like a ideal setup for maximum grip in the corners but it also reduce's feedback..it'll snap oversteer without warning..and it'll happen when you least expect it...and it happen's mostly on car's with a short wheelbase

another problems is waddle..waddle is the vehicle suddenly breaking traction and the vehicle's weight keep's shifting back and forth..preventing the tires from locking on to the road.

if you play gran turismo 3..the car's have little waddle..in gran turismo 4..the car physic's are completly different..all car's waddle like a bitch..

to combat waddle..i tihnk precise operation of the steering is needed..
if your car waddle's and you panic and countersteer but overcompensate, you've shifted the weight to the other side and now it's waddling again..

a pro would have found a way to get out of this situation by doing a reverse 180.

this is why car's from the factory handle better..or at least safer..
they warn you of the car's limit while you're entering a corner..

[wilburisthecoolest]

ah what??

Anyways ive found my current set up, B&G race springs and KYB struts, provide a very good supension with lots of feedback. i can feel my car start to slide and can easily slide the back end out with just a tad more throttle (think trying to weild the fucker to the floor) and some tighter steering input. I can start and hold about a 15 degree drift. Anymore and it becomes unpredicable.

When i had coilovers it was stupid touchy.

Stock supension i couldnt get the back end to come out at all.

[bh206]

cars are designed to be understeer prone because it makes them "safer" to drive.

So we all mod our cars for better handling and it usually makes them oversteer prone (that and the driver still drives like it's understeer prone). The guys who are spinning out.. can't handle their cars as well as they think they can.


Spinning out on the track isn't bad.. but oh right.. these people who "lose" their cars due to snap oversteer were trying to hit that on-ramp faster than last time.. and pushing their cars on city streets.

[zeroindigo]

*SNAP* oversteer, losing the rear tires in other words, is typical with rear wheel drive cars turning with too much power on, or a light front wheel drive braking and turning.

weight transfer is one issue, grip is another.

i dont play racing games, i hate the physics in all of them, but in real life snap oversteer in a fwd is not usually the car's fault, I had this happen because of rubber(great up front, crap in the rear) because of road conditions(sand on white pavement) and poor driving skills(braking in a turn, panick braking).

[andy]

most accent owners will never have to worry about oversteer issues unless they have setup the car to do so.

my daily driven lc will only oversteer under trail braking at speed and even then its never been what you would call "snap" oversteer

any tight transitions, its all understeer, the only other way I can get it to rotate is with left foot braking and even then it only works when I can get some traction from the front tires. This is in autocross situations only, I never push hard enough on the street to ever have to worry about much rotation but for everyday driving it is fairly neutral with a good amount of grip and pretty good stability at speed even in the rain.

everything said above is with this setup:
ksport coilovers(1 turn from full stiff front/full stiff in rear(race)full soft front and rear(street))
psc rear sway bar(full stiff)
205/40/16 kumho spts (30-38 psi depending on temps)
-2.75 camber front
-2.0 camber rear
zero toe front and rear

Now my 99 x3 turbo is a different story when not setup right
at my last autocross with it I had one clean run out of 5 with three off courses from either spinning in slaloms or sliding off course sideways

setup from june event:
ksports(full stiff front and rear)
psc rear bar (full stiff)
no front sway bar
205/50/15 kumho v710s(32 psi front and rear)
-3.0 camber front
-2.0 camber rear
zero toe front and rear
full yaya polyurethane bushings front and rear

if you really want rotation don't run a front sway bar or run a custom really big rear bar or really high spring rates in the rear. Its definately not fast on higher speed courses but on tighter courses it could come in handy. I wanted to try it out but it bit me in the ass, I had too much body roll in the front which caused the rear to lift wheels and lose grip resulting in said spins mostly in slaloms or high speed(70+mph) transitions.

if anyone has any questions about setup, I've been tinkering with both the accents for the past year trying to get thinks dialed in i'll try to pass on what has worked for me and what has not.

[MechaniX_034]

To correct it, I'd suggest attending a high-performance driving course. Weight balance and weight distribution control are very important things that influence a car's cornering attitude. Transitioning roughly can unsettle a car, and that's the major cause of "snap-oversteer."

So basically its:

• Be smooth
• Finish your braking before going down a gear or two
• Finish going down in the gears before you start turing the car in
• Turn the car win with minimal steering movement
• Be OFF the brakes completely before you begin turning the car in.

This is the safest way. Do NOT try to trail-brake the car in unless you're used to it.

[dmonkyking]

Originally Posted by andy

most accent owners will never have to worry about oversteer issues unless they have setup the car to do so.

my daily driven lc will only oversteer under trail braking at speed and even then its never been what you would call "snap" oversteer

any tight transitions, its all understeer, the only other way I can get it to rotate is with left foot braking and even then it only works when I can get some traction from the front tires. This is in autocross situations only, I never push hard enough on the street to ever have to worry about much rotation but for everyday driving it is fairly neutral with a good amount of grip and pretty good stability at speed even in the rain.

everything said above is with this setup:
ksport coilovers(1 turn from full stiff front/full stiff in rear(race)full soft front and rear(street))
psc rear sway bar(full stiff)
205/40/16 kumho spts (30-38 psi depending on temps)
-2.75 camber front
-2.0 camber rear
zero toe front and rear

Now my 99 x3 turbo is a different story when not setup right
at my last autocross with it I had one clean run out of 5 with three off courses from either spinning in slaloms or sliding off course sideways

setup from june event:
ksports(full stiff front and rear)
psc rear bar (full stiff)
no front sway bar
205/50/15 kumho v710s(32 psi front and rear)
-3.0 camber front
-2.0 camber rear
zero toe front and rear
full yaya polyurethane bushings front and rear

if you really want rotation don't run a front sway bar or run a custom really big rear bar or really high spring rates in the rear. Its definately not fast on higher speed courses but on tighter courses it could come in handy. I wanted to try it out but it bit me in the ass, I had too much body roll in the front which caused the rear to lift wheels and lose grip resulting in said spins mostly in slaloms or high speed(70+mph) transitions.

if anyone has any questions about setup, I've been tinkering with both the accents for the past year trying to get thinks dialed in i'll try to pass on what has worked for me and what has not.

I also have the ksport coilover setup with a front Evofusion strut bar. I have mine dialed in at full stiff on front and back (seems to be too bouncy on soft setting for me). I never race on the track though, would like to. I was thinking about getting some sway bars, especially for the back for stiffer cornering. How have you noticed the handling compared to running just coilovers and coilovers/swaybars? Also, I have my setup pretty darn low and I tend to scrape the RR tire on the wheelwell, ha. Wasn't sure if there was a better way to deal with that issue too besides lifting the back up or cutting my wheelwells. You think thicker sway bars may help? Any advice?

[andy]

I haven't had rubbing problems for awhile now

possibilities are:

your rubbing on the inside of the rear fender wells or rubbing on the dreaded rear bumper mount

I trimmed my inner fenders a couple of years ago to try to solve rubbing issues with my old tires and eibach/kyb suspension. The problem only went away when I went with a slightly smaller tire.

Once I installed the ksports I eyed my ride height around the same as the eibachs but dropped maybe another half an inch in the rear.

I run quite a bit of negative camber in the rear which might solve your problem as well. If you don't want to run as much camber, you are going to be stuck trimming your inner fender lips and the mount for the rear bumper(you will know what i'm talking about when you see it).

If none of that works your going to need to raise the rear.

A rear sway bar is still one of the best things that i've done to my car. It is such a noticeable difference that you will not want to drive without again. You will immediately feel the rear of the car doing more work even under light turning. I wouldn't suggest an aftermarket front bar unless you plan on doing some track days and want the added safety of understeer in long sweepers. For the street the adjustable psc bar is a great addition to your coilovers and a good step in making the car more neutral.

[dmonkyking]

Originally Posted by andy

I haven't had rubbing problems for awhile now

possibilities are:

your rubbing on the inside of the rear fender wells or rubbing on the dreaded rear bumper mount

I trimmed my inner fenders a couple of years ago to try to solve rubbing issues with my old tires and eibach/kyb suspension. The problem only went away when I went with a slightly smaller tire.

Once I installed the ksports I eyed my ride height around the same as the eibachs but dropped maybe another half an inch in the rear.

I run quite a bit of negative camber in the rear which might solve your problem as well. If you don't want to run as much camber, you are going to be stuck trimming your inner fender lips and the mount for the rear bumper(you will know what i'm talking about when you see it).

If none of that works your going to need to raise the rear.

A rear sway bar is still one of the best things that i've done to my car. It is such a noticeable difference that you will not want to drive without again. You will immediately feel the rear of the car doing more work even under light turning. I wouldn't suggest an aftermarket front bar unless you plan on doing some track days and want the added safety of understeer in long sweepers. For the street the adjustable psc bar is a great addition to your coilovers and a good step in making the car more neutral.

sweet, thanks Andy for your advice. I'll probably end up bringing the back up a little as I do have like no gap between the tire and wheelwell so. Also, I was checking out that PSC adjustable swaybar for awhile, was s&h a killer for you?

[andy]

shipping wasn't too bad, it did take about a month to get here though. It is worth the wait though. If someone else in the states made a bar i'd say go with that, but since this is really our only option, the price isn't outrageous.